This invention relates to a separative personal computer (referred to as PC, hereinafter) that is used for an external storage unit of a PC and the like, and of which a display unit and data processing block can be connected/disconnected that is used.
FIG. 12 is a block diagram showing a conventional embodiment of a PC card construction with a display unit, and FIG. 13 is a perspective view showing a schematic structure of the PC card with a display unit.
In FIG. 12 and FIG. 13, the PC card with a display unit is of PCMCIA specifications, of which thickness is 3.3 mm or 5 mm, at the most 10 mm. And the PC card comprises a connector 1 equipped with a contact pin with PCMCIA specifications, a PC connection control section (PCMCIA controller) 2 for controlling data transmission/reception (connection) with a PC (not shown in the figure), a memory 3 for performing data transmission/reception with the PC, and a CPU 4 for controlling each section of the PC card with a display unit.
The PC card also comprises a switching detection section 5 for detecting various instruction operations and the like, a switch 6 for performing various instruction operations, a power source 7 using a chargeable battery for supplying direct current to each section of the PC card with a display unit, a liquid-crystal display (referred to as LCD, hereinafter) 8 for displaying processing data on its screen, and a display unit control section 9 for controlling screen display for the LCD 8.
Next operations of the conventional embodiment are explained.
In FIG. 12 and FIG. 13, in use of the PC card with a display unit, the connector 1 is connected to the connection section (slot) of the PC. When a setting operation by the switch 6 is input to the CPU 4, the CPU 4 performs control operation based on the instruction. For example, the PC connection control section 2 and the memory 3 control a data transmission instruction and the like, and the data is transmitted to the PC connected to the connector 1 via the connector 1. At the same time, the data is displayed on the screen of the LCD 8 by the data display unit control section 9 based on the operation of the switch 6.
In addition, the CPU 4 controls to ingest data from the connected PC through the connector 1 and the PC connection control section 2. A PC card with a display unit operating in this way may be equipped in a radio selective calling unit, a radio portable phone and a portable information terminal and the like. In these cases the PC card may be used without being connected to the PC. For this purpose, the LCD 8 is provided for various screen displays.
The PC card with a display unit has a thickness of 3.3 mm, 5 mm or 10 mm when the PC card meets PCMCIA specifications. The connector 1 is provided to be connected to the PC connection section corresponding to the thickness. Extension sections such as the switch 6 and the LCD 8 project from the PC connection section so as to facilitate screen viewing and operations. One of the conventional embodiments of a PC card with a display unit like this is disclosed in JP-U-No.139581/1989 "IC card with display function". In the embodiment of JP-U-No.139581/1989, each part of a divided a plurality of display section comprises a liquid-crystal display element of a glass substrate. In this way the thickness of the PC card with PCMCIA specifications is regulated so as to be connected to the connection section of the PC, therefore a display unit and an operation section required for a portable unit cannot be set in the card. In other words the display unit and the operation section are set as an extension part and consequently the dimension becomes large and the card is difficult to be shaped to a portable form.
A radio section and a display section are not built in a PC card with a display unit in the above-mentioned conventional embodiment but are set on the outside of the PC connection section (slot). Therefore a signal line from the display section passes through the radio section and, for example, a display processing clock signal is mixed into a processing signal of the radio section. As a result a data error is generated. When the IC card with a display function in the above-mentioned embodiment is used in the same way, the same trouble is caused.